In a typical well completion it may be desirable to isolate one pay zone from another so that only one zone is produced at a time. Such isolation is typically accomplished by the placement of well packers in the well bore on either side of each pay zone. The sequence of production of multiple pay zones which are tapped individually is typically dictated by well and reservoir conditions. Such conditions may include different fluid loss characteristics from zone to zone, downhole well pressures which differ from zone to zone, and differing mineralogic conditions from zone to zone.
In addition to reservoir and well conditions, the cost of completion is typically an overriding factor because each packer which is used to isolate the pay zones from each other is usually relatively expensive. Also, the time it takes to complete a well is partially determined by the expense associated with renting drilling rigs, which is costly. Therefore any completion method which can reduce the time required to complete a well provides a net savings to the producer.